This research is a panel study of the impact of psychological distress on the use of physician services among a Medicare population enrolled in an HMO. Fifteen hundred Medicare enrollees will be interviewed every two months. The initial interview will provide data on life events, strain, and demoralization, as well as data on social networks and supports and a number of background characteristics. Events, strain, and demoralization will also be measured at the six month and final interviews. Interim interviews will provide data on symptoms and responses to symptoms. Data from the initial interview will be used to analyze symptom responses, including how symptoms are appraised, whether or not a physician visit should be made for symptoms and whether or not a physician visit was actually made. In addition, data from the encounter forms at the HMO will be analyzed for all visits made by the sample. These data include ICDA-9 diagnostic codes, RVS procedures, prescriptions and specialty referrals. The research is intended to provide data on three questions: 1) What is the impact of psychological distress on a Medicare population's demand for care in a setting in which there is minimal financial obligation associated with such demand; 2) To what extent do physicians respond to the visits of the psychologically distressed aged differently than they respond to the visits of the nondistressed aged; and 3) How likely is it that offset strategies based on the promotion of social support among the aged can reduce demand for care in an HMO.